Class EventListenerList

A class that holds a list of EventListeners. A single instance
can be used to hold all listeners (of all types) for the instance
using the list. It is the responsiblity of the class using the
EventListenerList to provide type-safe API (preferably conforming
to the JavaBeans spec) and methods which dispatch event notification
methods to appropriate Event Listeners on the list.
The main benefits that this class provides are that it is relatively
cheap in the case of no listeners, and it provides serialization for
event-listener lists in a single place, as well as a degree of MT safety
(when used correctly).
Usage example:
Say one is defining a class that sends out FooEvents, and one wants
to allow users of the class to register FooListeners and receive
notification when FooEvents occur. The following should be added
to the class definition:

foo should be changed to the appropriate name, and fireFooXxx to the
appropriate method name. One fire method should exist for each
notification method in the FooListener interface.

Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing. As of 1.4, support for long term storage
of all JavaBeans™
has been added to the java.beans package.
Please see XMLEncoder.

Field Detail

listenerList

Constructor Detail

EventListenerList

Method Detail

getListenerList

Passes back the event listener list as an array
of ListenerType-listener pairs. Note that for
performance reasons, this implementation passes back
the actual data structure in which the listener data
is stored internally!
This method is guaranteed to pass back a non-null
array, so that no null-checking is required in
fire methods. A zero-length array of Object should
be returned if there are currently no listeners.
WARNING!!! Absolutely NO modification of
the data contained in this array should be made -- if
any such manipulation is necessary, it should be done
on a copy of the array returned rather than the array
itself.